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Effects of NHC-backbone substitution on efficiency in ruthenium-based olefin metathesis.

ABSTRACT: A series of ruthenium olefin metathesis catalysts bearing N-heterocyclic carbene (NHC) ligands with varying degrees of backbone and N-aryl substitution have been prepared. These complexes show greater resistance to decomposition through C-H activation of the N-aryl group, resulting in increased catalyst lifetimes. This work has utilized robotic technology to examine the activity and stability of each catalyst in metathesis, providing insights into the relationship between ligand architecture and enhanced efficiency. The development of this robotic methodology has also shown that, under optimized conditions, catalyst loadings as low as 25 ppm can lead to 100% conversion in the ring-closing metathesis of diethyl diallylmalonate.

SUBMITTER: Kuhn KM

PROVIDER: S-EPMC2679506 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Effects of NHC-backbone substitution on efficiency in ruthenium-based olefin metathesis.

Kuhn Kevin M KM Bourg Jean-Baptiste JB Chung Cheol K CK Virgil Scott C SC Grubbs Robert H RH

Journal of the American Chemical Society 20090401 14

A series of ruthenium olefin metathesis catalysts bearing N-heterocyclic carbene (NHC) ligands with varying degrees of backbone and N-aryl substitution have been prepared. These complexes show greater resistance to decomposition through C-H activation of the N-aryl group, resulting in increased catalyst lifetimes. This work has utilized robotic technology to examine the activity and stability of each catalyst in metathesis, providing insights into the relationship between ligand architecture and ...[more]

PMID: 19351207

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